The dynamic events occurring within the Clinical Center's Medical Intensive Care Unit are monitored by a unique multiple-computer system. Capabilities of the system include online data acquisition and analysis, medical recordkeeping, tabular and graphical data displays, and feedback control, as required in support of patient care and research protocols. Elements include a minicomputer-based Patient Data Management Subsystem, a Software Development Subsystem, and a Medical Mass Spectrometer Subsystem.